1. Field of Invention
The present invention relates to an oscillation circuit and an oscillation system, and more particularly to an oscillation circuit capable of generating a high-precision clock and an oscillation system thereof.
2. Description of Related Arts
An oscillator is an electronic element for generating a repeating electronic signal which is usually a sine wave or a square wave. A circuit constituted by the oscillator is called an oscillation circuit. And the oscillation circuit is an electronic circuit or device capable of converting a direct current into an alternating current with a certain frequency, and outputting the alternating current.
In general process conditions, it is difficult to generate a high-precision clock via the oscillation circuit, because the characteristic of an element in the oscillation circuit varies with the process corner or the temperature, and the variation often causes an clock frequency deviation up to ±20% in the oscillation circuit. Thus, it is necessary to provide an oscillation circuit capable of generating the high-precision clock and an oscillation system thereof.